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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Random unsigned integer

Terminal - Random unsigned integer
echo $RANDOM
2010-11-09 09:57:44
User: depesz
Functions: echo
Random unsigned integer

works at least in bash. returns integer in range 0-32767. range is not as good, but for lots of cases it's good enough.


There are 3 alternatives - vote for the best!

Terminal - Alternatives
echo $(openssl rand 4 | od -DAn)
od -N 4 -t uL -An /dev/random | tr -d " "
2010-11-09 07:57:16
User: hfs
Functions: od tr
Tags: random

Reads 4 bytes from the random device and formats them as unsigned integer between 0 and 2^32-1.

curl -s "https://www.random.org/cgi-bin/randbyte?nbytes=4" | od -DAn
2010-11-09 18:26:24
Functions: od
Tags: random

Grab 4 bytes from www.random.org over ssl and format them as an integer

Know a better way?

If you can do better, submit your command here.

What others think

And to narrow it down to a specfic range, e.g. 0-255:

echo $((RANDOM%256))
Comment by flatcap 311 weeks ago

Your point of view

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